Search results for " Biochemistry"

The Effect of Bialaphos on Ammonium-Assimilation and Photosynthesis I. Effect on the Enzymes of Ammonium-Assimilation

1989

Abstract In this investigation, the effect of bialaphos (phosphinothricyl-alanyl-alanine) on the enzymes involved in NH4 +-assimilation - glutamine synthetase, glutamine-2-oxoglutarate aminotransferase, glutamate dehydrogenase - is examined and compared to the effect of phosphinothricin (glufosinate) on the same enzymes. Bialaphos was given to whole plants (in vivo) and to leaf homogenate (in vitro). The investigation showed that bialaphos has an inhibiting effect on glutamine synthetase in vivo, but not in vitro. In contrast to this, phosphinothricin inhibits glutamine synthetase in vitro as well as in vivo. It was found that bialaphos, similar to phosphinothricin, does not inhibit glutami…

Phenolic Compounds from Lactuca viminea L.

1992

Abstract The aerial part of Lactuca viminea L. was examined for the presence of phenolic compounds. Six different flavonoids were isolated and identified by UV spectra, TLC, HPLCDAD , 1H NMR and 13C NMR. They were identified as apigenin, luteolin, quercetin, luteolin-7-O-glucoside, quercetin-3-O-glucoside and luteolin-7-O-glucuronide-6″methyl ester. Three phenolic acids were also detected: caffeic, ferulic and chlorogenic acid.

A novel heterocyclic sulfonamide: N-benzyl-5-[N-benzyl-N-(tert-butyloxycarbonyl)amino]-N-(tert-butyloxycarbonyl)-1,3,4-thiadiazole-2-sulfonamide

2000

The title compound, C(26)H(32)N(4)O(6)S(2), is a heterocyclic sulfonamide which is a 1,3,4-thiadiazole derivative. Structural data for this compound are compared with those of related compounds.

Omega-3 PUFAs and gut microbiota: A preventive approach for colorectal cancer

2021

The influence of diet on the composition of the intestinal microbiota and related pathologies has been known for some time. Some classes of nutrients, such as fatty acids belonging to the omega 3 series, have particular effects on the bacteria that make up the intestinal microbiota. ω-3 PUFAs affect the gut microbiota in three different ways: by modulating the type and abundance of intestinal bacteria, by regulate SCFAs levels, and by alter the levels of proinflammatory mediators. Through these modalities, ω-3 PUFAs could be useful for the prevention of intestinal diseases such as Colorectal Cancer (CRC). The ability of ω-3 PUFAs to modulate the intestinal inflammatory response, to preserve…

Der Verteilungsraum von physikalisch gelöstem Sauerstoff in wäßrigen Lösungen organischer Substanzen / The Distribution Space of Physically Dissolved…

1976

Abstract In order to evaluate the distribution of molecular oxygen in biological systems, the oxygen solubility (ml/ml atm) at 37 °C in aqueous solutions of thirty organic substances with different concentrations was measured by the classical Van Slyke principle. The oxygen solubility always (with the exception of hemoglobin) decreases exponentially with increasing concentration of the respective substance. In all cases this behavior is described highly significant by a simple empiric exponential function, when the substance concentration as well as the oxygen solubility of pure water is given. The influence of one substance on oxygen solubility contributes additively to the over-all solubi…

Formation of α-ω(4,7,10,13-pentaoxa-16-azacyclooctadecane) hexadecane micelles in aqueous solution – effect of HCl addition

2003

The structure of aggregates of a new bolaform surfactant [α-ω (4,7,10,13-pentaoxa-16-azacyclooctadecane) hexadecane] in neat aqueous solution has been investigated by small-angle neutron scattering. Preliminary data analysis unequivocally indicates that globular micelles are formed. This finding has been confirmed by the analysis of data obtained upon addition of hydrochloric acid. The observed significant reduction of micelle aggregation number has been attributed to the peculiar complexing ability of the two aza-crown ether units in the surfactant molecule; this is in line with information inferred from the complexation of ions into the non alkylated azacrown ethers. As a consequence of h…

Isolation, separation and quantification of metabolites of the carcinogenic polycyclic aromatic hydrocarbon dibenz(a,h)anthracene

1986

The Effect of Bialaphos on Ammonium-Assimilation and Photosynthesis II. Effect on Photosynthesis and Photorespiration

1989

Abstract The application of bialaphos (phosphinothricyl-alanyl-alanine) effects a quick photosynthesis inhibition under atmospheric conditions (400 ppm CO2, 21% O2). However, under conditions (1000 ppm CO2, 2% O2) under which photorespiration cannot occur there is no photosynthesis inhibition. In the previous investigation it could be shown that bialaphos splits in plants into phosphinothricin and alanine. The inhibition of glutamine synthetase through freed phosphinothricin results in an NH4 +-accumulation and a decrease in glutamine. With the addition of glutamine, photosynthesis inhibition by bialaphos can be reduced. An NH4 +-accumulation takes place under atmospheric conditions as well…

2(S)-Amino-3-[1H-imidazol-4(5)-yl]propyl cyclohexylmethyl ether dihydrochloride and 2(S)-amino-3-[1H-imidazol-4(5)-yl]propyl 4-bromobenzyl ether dihy…

2000

(Cyclohexylmethyloxymethyl)(1H-imidazol-4-iomethyl)-(S)-ammonium dichloride, C(13)H(25)N(3)O(+).2Cl(-), and (4-bromobenzyl)(1H-imidazol-4-iomethyl)-(S)-ammonium dichloride, C(13)H(18)BrN(3)O(+).2Cl(-), are model compounds with different biological activities for evaluation of the histamine H3-receptor activation mechanism. Both title compounds occur in almost similar extended conformations.

Gas chromatographic study of acetyl derivates of chlorinated guaiacols

1982

The gas chromatography of acetyl derivatives of guaiacol and all chlorinated guaiacols has been studied on SE-30, OV-351 and Carbowax 20M capillary columns. The retention order and relative retention times under isotermal and temperature-programmed conditions are discussed. Different retention times for all mono- and dichloro compounds have been observed on the SE-30 column. However, all trichloroguaiacol isomers were separated only on polar columns. The best overall temperature-programmed separations have been achieved on an SE-30 capillary column.